lunacy

[loo-nuh-see] /ˈlu nə si/
noun, plural lunacies.
1.
insanity; mental disorder.
2.
intermittent insanity, formerly believed to be related to phases of the moon.
3.
extreme foolishness or an instance of it:
Her decision to resign was sheer lunacy.
4.
Law. unsoundness of mind sufficient to incapacitate one for civil transactions.
Origin
1535-45; lun(atic) + -acy
Synonyms
1. derangement, dementia; craziness, madness, mania, aberration. 3. folly, stupidity.
Antonyms
1, 2. rationality, sanity.
Examples from the web for lunacy
  • His descent into madness is rapid but not sudden, and his lunacy seems inevitable.
  • The first is excellent on the cosmology and physics interface and the second is great at debunking pseudoscience lunacy de jour.
  • Extending into the private sector a policy that has been a disaster in the public sector is lunacy.
  • Our government's policies on drugs are sheer lunacy.
  • In fieldwork, strangers thrown together often find common ground in bouts of functional lunacy.
  • The idea that one method fits all is a bit of lunacy.
  • It is lunacy to submit our children and the children of our neighborhood to preventable diseases.
  • The quotes are not implausible, it is the interpretation that is lunacy.
  • All three are always there, but it is the last that pushes lunacy in the other two.
  • lunacy in a family is not a particularly funny thing, nor does it seem fitting and tasteful as a matter to be treated as farce.
British Dictionary definitions for lunacy

lunacy

/ˈluːnəsɪ/
noun (pl) -cies
1.
(formerly) any severe mental illness
2.
foolishness or a foolish act
Word Origin and History for lunacy
n.

1540s, "condition of being a lunatic," formed in English from lunatic + -cy. Originally in reference to intermittent periods of insanity, such as were believed to be triggered by the moon's cycle. The Old English equivalent was monaðseocnes "month-sickness."